====== HiMD device control command (0xC2) ======

The device control command is 12 bytes (0x0C), and depending on subcommand, intiates a data transfer from or to the device. The layout of the command block is

  Byte 00: Command (0xC2)
  Byte 01: Unknown, sent as zero (maybe LUN?)
  Byte 02: For some subcommands: Application ID (0 == General?, 1 == MD Audio?, 2 == UMD Audio?)
  Byte 03: subcommand
  Byte 04: For some subcommands: Flag bits
  Byte 05: For the switch interface command: Delay
  Byte 06: unused, sent as zero
  Byte 07: Set explicitly to zero for Get Leaf ID - Some Index?
  Byte 08: Byte count of data transfer
  Bytes 09-0B: unused

=== Subcommand 00: Erase HiMD ===
  * Application ID: 0
  * Used fields: flags.
    * Bit 0: IMMED ("immediate": finish SCSI handling before command finishes - must be set on RH-1)
    * Bit 1: FUA ("force unit access": write now, don't cache)

This command completely blanks the medium. This is not possible with Hi-MD 1GB media, as the Disc ID is read-only. Standard MD media completely blanked are usable in standard MD devices. This is the only way getting rid of Hi-MD format on a standard MD medium.

=== Subcommand 01: Format HiMD ===
  * Application ID: 0
  * Used fields: flags.
    * Bit 0: IMMED ("immediate": finish SCSI handling before command finishes - must be set on RH-1)
    * Bit 1: FUA ("force unit access": write now, don't cache)
    * Bit 2: NOFS (Don't generate FAT FS? - must be cleared on RH-1)

This command just reinitializes the Hi-MD data structures on the Medium, but it doesn't remove the Hi-MD layout from it. It generally keeps the Disc ID, as this data is stored *outside* of the area accessible using normal read/write instructions, and only this area is reinitialized.

=== Subcommand 0E: Begin ICV Transaction ===
  * Application ID: 0
  * Used fields: none

If the command is correctly understood, it starts a transaction that updates FAT, directory and the master ICV all at the same time, or none at all. See [[HiMDDownload]], at timestampe 84.6. The transaction is committed by the new ICV at timestamp 93.2

=== Subcommand 0F: Recommend Synchronize Cache ===
  * Application ID: 0
  * Used fields: none

=== Subcommand 10: Switch Interface ===
=== Subcommand 11: Get Leaf ID ===
=== Subcommand 20: Load Audio TOC ===
  * Application ID: 1 or 2
  * Used fields: none

=== Subcommand 21: Pause Audio ===
  * Application ID: 1 or 2
  * Used fields: none

=== Subcommand 22: Play Audio ===
  * Application ID: 1 or 2
  * Used fields: none

=== Subcommand 23: Scan Audio ===
  * Application ID: 1 or 2
  * Used fields: flags.
    * Bit 7: unknown function

=== Subcommand 24: Search Audio ===
=== Subcommand 25: Seek Audio ===
=== Subcommand 26: Stop Audio ===
=== Subcommand 40: Read Defect List ===
=== Subcommand 41: Read Zone List ===
=== Subcommand 50: Get Time ===
  * Application ID: 0
  * Used fields: data size, should be 7
Reads a 7-byte data packet from the Hi-MD unit with the following layout:

  Byte 00: Flags. Bit 7 = Ex; Bit 6 = Ef; Bit 5 = WP (write protect?)
  Byte 01: second
  Byte 02: minute
  Byte 03: hour
  Byte 04: day
  Byte 05: month
  Byte 06: year

=== Subcommand 60: Read Audio Status ===
=== Subcommand 90: Set Time ===
=== Subcommand A0: Play audio parts ===